powerpc/powernv: Enable reading and updating of system parameters

This patch enables reading and updating of system parameters through
OPAL call.

Signed-off-by: Neelesh Gupta <neelegup@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

diff --cc arch/powerpc/include/asm/opal.h
Simple merge

diff --cc arch/powerpc/platforms/powernv/Makefile
Simple merge

diff --cc arch/powerpc/platforms/powernv/opal-sysparam.c
Simple merge

diff --cc arch/powerpc/platforms/powernv/opal-wrappers.S
Simple merge

diff --cc arch/powerpc/platforms/powernv/opal.c
Simple merge